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                <tr><td id="docbody"><h1><a href="http://www.dsource.org/projects/tango/browser/trunk/tango/math/Bessel.d?rev=3791">tango.math.Bessel</a></h1>
                
<font color="black">Cylindrical Bessel functions of integral order.</font><br><br>
<b>License:</b><br>
BSD style: see <a href="http://www.dsource.org/projects/tango/wiki/LibraryLicense">license.txt</a><br><br>
<b>Authors:</b><br>
Stephen L. Moshier &#40;original C code&#41;. Conversion to D by Don Clugston<br><br>
<dl>
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<dt><span class="decl"><li>real <span class="currsymbol"><a href="http://www.dsource.org/projects/tango/browser/trunk/tango/math/Bessel.d?rev=3791#L100">cylBessel_j0</a></span>
<script>explorer.outline.addDecl('cylBessel_j0');</script>(real <span class="funcparam">x</span>);</li></span></dt>
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<dd>
<font color="black">Bessel function of order zero</font><br><br>
<font color="black">Returns Bessel function of first kind, order zero of the argument.
 </font><br><br></dd>
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<dt><span class="decl"><li>real <span class="currsymbol"><a href="http://www.dsource.org/projects/tango/browser/trunk/tango/math/Bessel.d?rev=3791#L144">cylBessel_y0</a></span>
<script>explorer.outline.addDecl('cylBessel_y0');</script>(real <span class="funcparam">x</span>);</li></span></dt>
<script>explorer.outline.writeEnabled = false;</script>
<dd>
<font color="black">Bessel function of the second kind, order zero
 Also known as the cylindrical Neumann function, order zero.</font><br><br>
<font color="black">Returns Bessel function of the second kind, of order
 zero, of the argument.
 </font><br><br></dd>
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<dt><span class="decl"><li>real <span class="currsymbol"><a href="http://www.dsource.org/projects/tango/browser/trunk/tango/math/Bessel.d?rev=3791#L218">cylBessel_j1</a></span>
<script>explorer.outline.addDecl('cylBessel_j1');</script>(real <span class="funcparam">x</span>);</li></span></dt>
<script>explorer.outline.writeEnabled = false;</script>
<dd>
<font color="black">Bessel function of order one</font><br><br>
<font color="black">Returns Bessel function of order one of the argument.
 </font><br><br></dd>
<script>explorer.outline.writeEnabled = true;</script>
<dt><span class="decl"><li>real <span class="currsymbol"><a href="http://www.dsource.org/projects/tango/browser/trunk/tango/math/Bessel.d?rev=3791#L260">cylBessel_y1</a></span>
<script>explorer.outline.addDecl('cylBessel_y1');</script>(real <span class="funcparam">x</span>);</li></span></dt>
<script>explorer.outline.writeEnabled = false;</script>
<dd>
<font color="black">Bessel function of the second kind, order zero</font><br><br>
<font color="black">Returns Bessel function of the second kind, of order
 zero, of the argument.
 </font><br><br></dd>
<script>explorer.outline.writeEnabled = true;</script>
<dt><span class="decl"><li>real <span class="currsymbol"><a href="http://www.dsource.org/projects/tango/browser/trunk/tango/math/Bessel.d?rev=3791#L360">cylBessel_jn</a></span>
<script>explorer.outline.addDecl('cylBessel_jn');</script>(int <span class="funcparam">n</span>, real <span class="funcparam">x</span>);</li></span></dt>
<script>explorer.outline.writeEnabled = false;</script>
<dd>
<font color="black">Bessel function of integer order</font><br><br>
<font color="black">Returns Bessel function of order n, where n is a
 &#40;possibly negative&#41; integer.<br><br> The ratio of jn&#40;x&#41; to j0&#40;x&#41; is computed by backward
 recurrence.  First the ratio jn/jn-1 is found by a
 continued fraction expansion.  Then the recurrence
 relating successive orders is applied until j0 or j1 is
 reached.<br><br> If n = 0 or 1 the routine for j0 or j1 is called
 directly.<br><br> </font><br><br>
<font color="red">BUGS:</font><br>
Not suitable for large n or x.<br><br></dd>
<script>explorer.outline.writeEnabled = true;</script>
<dt><span class="decl"><li>real <span class="currsymbol"><a href="http://www.dsource.org/projects/tango/browser/trunk/tango/math/Bessel.d?rev=3791#L439">cylBessel_yn</a></span>
<script>explorer.outline.addDecl('cylBessel_yn');</script>(int <span class="funcparam">n</span>, real <span class="funcparam">x</span>);</li></span></dt>
<script>explorer.outline.writeEnabled = false;</script>
<dd>
<font color="black">Bessel function of second kind of integer order</font><br><br>
<font color="black">Returns Bessel function of order n, where n is a
 &#40;possibly negative&#41; integer.<br><br> The function is evaluated by forward recurrence on
 n, starting with values computed by the routines
 cylBessel_y0&#40;&#41; and cylBessel_y1&#40;&#41;.<br><br> If n = 0 or 1 the routine for cylBessel_y0 or cylBessel_y1 is called
 directly.
 </font><br><br></dd>
<script>explorer.outline.writeEnabled = true;</script>
<dt><span class="decl"><li>double <span class="currsymbol"><a href="http://www.dsource.org/projects/tango/browser/trunk/tango/math/Bessel.d?rev=3791#L505">cylBessel_i0</a></span>
<script>explorer.outline.addDecl('cylBessel_i0');</script>(double <span class="funcparam">x</span>);</li></span></dt>
<script>explorer.outline.writeEnabled = false;</script>
<dd>
<font color="black">Modified Bessel function of order zero</font><br><br>
<font color="black">Returns modified Bessel function of order zero of the
 argument.<br><br> The function is defined as i0&#40;x&#41; = j0&#40; ix &#41;.<br><br> The range is partitioned into the two intervals [0,8] and
 &#40;8, infinity&#41;.  Chebyshev polynomial expansions are employed
 in each interval.
 </font><br><br></dd>
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<dt><span class="decl"><li>double <span class="currsymbol"><a href="http://www.dsource.org/projects/tango/browser/trunk/tango/math/Bessel.d?rev=3791#L557">cylBessel_i1</a></span>
<script>explorer.outline.addDecl('cylBessel_i1');</script>(double <span class="funcparam">x</span>);</li></span></dt>
<script>explorer.outline.writeEnabled = false;</script>
<dd>
<font color="black">Modified Bessel function of order one</font><br><br>
<font color="black">Returns modified Bessel function of order one of the
 argument.<br><br> The function is defined as i1&#40;x&#41; = -i j1&#40; ix &#41;.<br><br> The range is partitioned into the two intervals [0,8] and
 &#40;8, infinity&#41;.  Chebyshev polynomial expansions are employed
 in each interval.
</font><br><br></dd></dl></td></tr>
                <tr><td id="docfooter">
                        Based on the CEPHES math library, which is
            Copyright (C) 1994 Stephen L. Moshier (moshier@world.std.com). :: page rendered by CandyDoc. Generated by <a href="http://code.google.com/p/dil">dil</a> on Sat Aug  2 16:08:34 2008.
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